Refrigerator



Dec. 27, 1938.

e. HILGYER REFRIGERATOR Filed June 25, 1957 Patented Dec. 21. 1938 UNITED STATES REFRIGERATOR Raymond G. Hilger, Chicago, 111.

Application June 25, 1937, Serial No. 150,298

. J 2 Claims. The inventionrel'ates to refrigerators and more particularly to ventilating arrangements there-' One object of the present invention is to pro- 1 '6 vide a refrigerator embodying an improved ventilating arrangement of such character that a limited flow of fresh air through the cooling compartment is automatically induced during the operation of the refrigerator, this flow of fresh air serving to prevent food or the like within the compartment from becoming odoriferous and also to increase the relative humidity prevailing within the compartment.

A more speciflc'object of the invention is to provide a refrigerator having an improved ventilating arrangement in which a cooling element within the refrigerator is utilized to induce a flow of fresh air into the compartment and is also preferably utilized to induce a discharge flow of foul air from the compartment.

Further objects and advantages of the invention will become apparent as the following description proceeds and the features of novelty which characterize the invention are pointedout with particularity in the claims annexed to and forminga part of this specification.

For a better understanding of the invention, reference may be had to the accompanying draw- 4 ingin which Figure 1 is a perspective view of a refrigerator embodying the invention, parts of the refrigerator being broken away to betterillustrate the interior construction thereof. V Fig. 2 is a transverse sectional view in reduced .scale'along the line 2-2 in Fig. l, the shelving and drip pan being omitted from this view. For purposes of illustration, the invention has been shown and described herein as embodied in a refrigerator designed primarily for domestic 40 use but it will be understood by those skilled in the art that various features of the present invention areapplicable to a wide variety of other types ofrefrigerators, coolers; or display cases,

- the term refrigerator being used herein to refer to all of these types of devices. In the exemplary embodiment of the invention a refrigerator has been shown .in Fig. 1 provided with a cabinet "designated generallyby the numeral Ill and including inner and outer sheet metal shells I l and I2, respectively; separated by a layer of heat insulating material l3, thus forming an interiorly located heat insulated cooling or food storage compartment I4. Arectangular opening it in the front of this compartment is closed by a heat insulated door It. Food or other articles to'be cooled may be supported on reticulated shelving II; the open-work construction of which permits the free circulation of cooling air through the compartment. u

The storage compartment I4 is cooled by a 'suitable cooling element illustrated in the form of an elongated rectangular refrigerant evaporator I! located in the upper portion of the compartment. It will be noted that this evaporator is generally box-like in form and provides a sharp freezing chamber l9 therein in which ice trays or the like may be placed. Vaporizable 'liquid refrigerant may be supplied to the evaporator l8 from a suitable compressor-condenser unit (not shown) located in the lower portion of the cabinet beneath the compartment ll. It will be understood that other types of cooling'elements or sources of artificial. refrigeration may be utilized if desired.

In accordance with the present invention an improved form of ventilating arrangement has been provided for the storage compartment it which is adapted to supply a limited quantity of fresh air thereto. This ventilating arrangement includes a fresh air supply conduit communicating with the exterior of the compartment l4 and with the interior thereof at a discharge point located closely adjacent to and below the level of at least a portion of the cooling element l8. In the particular construction illustrated a fresh air supply conduit 2|! extends along the inner side of the rear wall of the compartment it from an inlet port 2| on' the outer wall of the cabinet and terminates in'a' pair of parallel connected branched conduits 22 which are disposed slightly J below but closely'adjacent to the lower lateral edges of the evaporator I8 and on opposite sides of a drip pan 28 positioned below the evaporator. A plurality of small restricted discharge ports or holes 24 (Fig. 2) is provided in the lower sides of each of the branched conduits 22 substantially throughout their lengths. The comparatively warm exterior air. flowing into the supply conduit 20 and itsbranches 22 is thus cooled-by the lower temperature air within the compartment It so. as'to induce a convectional flow of air from the. exterior of the cabinet to the interior thereof. To aid this action the conduits 20 and 22 are preferably made of metal having a high thermal conductivity. It will be noted that the discharge ports 22 are located below the level of the inlet port 2| so as to facilitate the gravital flow of the cooled fresh air within the conduit sections 20 and 22. In addition, the air within the compartmeat II which is cooled by the evaporator i8 flows downwardly from its side surfaces due to.

V air into the compartment.- The fresh air which is thus mixed with the cold air leaving the evaporator i8 raises its temperature only a small amount of the order of not more than 10 F. but at the same time, effects a marked increase in the relative humidity of the final mixture. The restricted character of the inlet conduits and ports described prevents such a heavy flow of ventilating air as would markedly decrease the efficiency of the refrigerator but nevertheless, a sufficient flow is permitted'so that under the preferred operating conditions, the relative humidity of the air within the storage compartment 14 will be approximately 80 to 85 per cent, which has been found to be particularly desirable for the preservation of foodstuffs.

. It is also desirable to remove foul'air from the interior of the storage compartment since the deterioration of foodstuffs is retarded if the gases generated during the early stages of deterioration are removed, and also odors emanating from. the foodstuffs are minimized. For this purpose, a foul air discharge conduit has been provided in whichconvectioncurrents are set up to facilitate the discharge of the foul air. In the preferred arrangement illustrated, an elongated discharge conduit 25' extends from an outlet port 26 on the exterior of the cabinet upwardly through the lower portion of the storage compartment l4 and terminates in a pair of parallel connected branch conduits 21 located in the top portion of the series of inlet ports or holes 28 are provided in;

the upper sides of the branch' conduit sections 21. The comparatively warm air in the top of the compartment l4 enters the discharge conduit sections 21 through the ports 28 and a gravitational flow therefrom downwardly through the thermal conductivity so that the air therein will be quickly cooled by the surrounding air in the lower portion of the compartment It.

In the operation of the refrigerator described above, the evaporator I8 is cooled by the vaporization of suitablerefrigerant to a temperature of approximately 20 F. The air surrounding the same is cooled to a temperature of-approximately 30 F. and moves downwardly due to gravity past the discharge ports 24 in the ventilating air supply conduits 22 as indicated by the arrows 29. A flow of fresh air is thus induced through: the supply conduit sections 20 and 22 as described above,

this fresh air being mixed with the cooled air which moves by gravity downwardly to the lower portion of the compartment It as indicated by Foodstuffs supported on thethe arrows 30. shelving H are consequently maintained at a tem-' perature of approximately 40 to 45 r'. The cooled air in the compartment which is warmed by the material stored therein again moves up-' wardly to the top portion of the compartment as indicated by the arrows 3| and then downwardly along the sides of the evaporator 18, displacing the air cooled by the latter. In this downward movement of the air toward the evaporator, a

portion of the air which has passed over the stored material enters the, discharge conduit ports 21. The air thus entering these ports flows by gravity through the conduits 2'| -and 25 and then out through the port 26, this flow being caused by cooling of the air within the conduit 25 as heretofore described. It will thus be seen that" a simple but effective and eflicient ventilating ar rangement has been provided which is adapted to efiect a marked increase in the freshness and purity of the air within the refrigerator compart ture cooling element disposed in the upper portion of said compartment, a fresh air supply conduit extending from the exterior of said compart-- ment'into the interior thereof and closely adjacent the lower portion of' said cooling element,

said supply conduit having a plurality of small discharge openings in the lower side thereof adjacent said cooling element and all located below at least a major portion of said element, whereby the air in said compartment cooled by said element moves downwardly by gravitational flow past said conduit 'entraining-fresh air discharged ing foul air from the interior of said compartment to'the exterior thereof.

from said holes therein, and means for discharg- 2. A refrigerator comprising, in combination, a

heat insulated food storage compartment, an elongated refrigerant evaporator disposed in the upper portion of said compartment, a fresh air supply conduit extending from the exterior of said compartment and having a pair of branched portions provided with small restricted discharge ports in the lower sides thereof and extendin along the lower lateral edges of said-evaporator V and a foul air discharge conduit having an outlet port located exteriorly of the cabinet and extending upwardly therefrom through the lower portion of the interior ofv said compartment to the upper portion thereof, said foul air discharge conduit terminating in a pair of branched conduit sections extending along the upper lateral edges of said evaporator and having inlet ports in the 7 upper sidesthereof in the path of the air in said WRAYMONDGHILIGER. 

